Psychometric adaptation of the Spanish version of the Brief Pittsburgh Sleep Quality Index in adolescents

Abstract Objective Good sleep quality is essential for adolescent health, yet sleep difficulties persist in this age group. The 6-item Brief Pittsburgh Sleep Quality Index (B-PSQI) was recently developed to improve sleep quality assessment, however, its validity in adolescents remains unexplored. This study examined the B-PSQI’s psychometric properties in Spanish adolescents and adapted the scoring method to age-specific sleep recommendations. Methods A cross-sectional study involving 1,065 adolescents (15–17 years; 56.8% female) was conducted in public high schools. Sleep quality was measured using the B-PSQI, the Insomnia Severity Index (ISI), the short Patient-Reported Outcomes Measurement Information System (PROMIS), and the Epworth Sleepiness Scale (ESS). Additionally, depression and anxiety were assessed using the Depression, Anxiety, and Stress Scales. Reliability, validity, and measurement invariance were analyzed. Results The B-PSQI global scores were 4.5 (SD = 1.9) for the original scoring method and 5.4 (SD = 2.8) for the age-adjusted. The age-adjusted B-PSQI showed satisfactory reliability (ω = 0.84) and concurrent, convergent, and discriminant validity (ISI rS = 0.67; PROMIS rS = 0.71; anxiety rS = 0.40; depression rS = 0.42; ESS rS = 0.29). Adequacy for one-factor structure (χ2(4) = 53.9; CFI = 0.97; TLI = 0.92; RMSEA = 0.108; SRMR = 0.05) and invariance across sexes were supported. Both B-PSQI scoring methods showed similar psychometric properties, but the original yielded a higher percentage of poor sleepers (43.1%; cutoff ≥5) than the age-adjusted version (41.9%; cutoff ≥6). Conclusions Findings suggest that the B-PSQI is a valid and reliable measure to assess adolescent sleep quality. Its scoring can be adjusted to provide age-specific criteria for good sleep. The B-PSQI has potential utility for screening sleep problems and facilitating overall health promotion in adolescents.